Simplify the following expression: $p = \dfrac{7a + 3}{4a - 10} \div \dfrac{1}{9}$
Solution: Dividing by a number is the same as multiplying by its inverse. $p = \dfrac{7a + 3}{4a - 10} \times \dfrac{9}{1}$ When multiplying fractions, we multiply the numerators and the denominators. $p = \dfrac{(7a + 3) \times 9} {(4a - 10) \times 1}$ $p = \dfrac{63a + 27}{4a - 10}$